Fitcat. A cat that truncates long lines.

fitcat.py

# Fitcat. A cat that truncates long lines.
import contextlib, os, shutil, sys
try:
    width = os.get_terminal_size(sys.stdin.fileno()).columns
except OSError:
    width = shutil.get_terminal_size().columns
with contextlib.ExitStack() as stack, contextlib.suppress(BrokenPipeError):
    for f in [stack.enter_context(open(fname)) for fname in sys.argv[1:]]:
        [print(line[:width].rstrip()) for line in f]